The lack of accurate measures of human capital formation often constrain investigations into the long-run determinants of growth and comparative economic development, especially in regions such as Africa. Using the reported age of criminals in the Courts of Justice records in the Cape Archive, this paper documents, for the first time, the levels of and trends in numeracy for inhabitants of the Cape Colony born between the seventeenth and early nineteenth centuries. Cape inhabitants included the native Khoe and San, European settlers, and imported slaves from other African regions and Asia. This hodgepodge of individuals allows a unique comparison between contemporaneous levels of 18th century development across three continents. By isolating those slaves born at the Cape, we also provide a glimpse into the dynamics of human capital transfer in colonial settings.